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ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#607469 | #8939. Permutation | UESTC_NLNS# | RE | 0ms | 0kb | C++14 | 1.0kb | 2024-10-03 14:59:36 | 2024-10-03 14:59:39 |
Judging History
answer
#include<bits/stdc++.h>
#define ll long long
using namespace std;
unordered_map<ll,int> mp;
const int N=1e6+5;
void answer(int x)
{
printf("! %d\n",x);
fflush(stdout);
return;
}
int pp,n;
int query(int l,int r)
{
if(l>=r)assert(0);
if(mp.find(1ll*r*N+l)!=mp.end()) return mp[1ll*r*N+l];
int x;
printf("? %d %d\n",l,r);
pp+=r-l+1;
assert(pp<=3*n);
fflush(stdout);
scanf("%d",&x);
mp[1ll*r*N+l]=x;
return x;
}
void solve(int l,int r)
{
if(l==r)
{
answer(l);
return;
}
int mid=(l+r)/2,lmid,x=query(l,r),y;
if(l+1==r)
{
if(x==l) answer(r);
else answer(l);
return;
}
if(x<=mid)
{
lmid=(r-l)*3.0/5+l;
if(lmid==r) lmid--;
y=query(l,lmid);
if(x==y) solve(l,lmid);
else solve(lmid+1,r);
}
else
{
lmid=(r-l)*2.0/5+l;
if(lmid==l) lmid++;
y=query(lmid,r);
if(x==y) solve(lmid,r);
else solve(l,lmid-1);
}
return;
}
int T;
int main()
{
scanf("%d",&T);
while(T--)
{
scanf("%d",&n);
solve(1,n);
mp.clear();
}
return 0;
}
Details
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Test #1:
score: 0
Runtime Error
input:
3 5 3 2 5 6 6
output:
? 1 5 ? 1 3 ? 4 5 ! 4 ? 1 6